Lantana camara.L (hereafter Lantana)was first introduced by the British intoIndia in 1807 as an ornamental plant. Since then the species has spread across the lengthand breadth of the country. Attempts to control Lantana in India have not been successful.In this study, we analysed the use of Lantana by local communities in southern India and identified the possible causes and consequences of its use through the use of a household survey of the socio-economic profile of the user and nonuser households and an analysis ofthe ecological history of the communities. Communities have been using Lantana for over 25-30 years and apparently such use was not prompted by external agencies. The characteristics of user and nonuser households were similar, except that Lantana users weremore literate and had a greater number of occupations per household than nonusers. Percapita income was similar between user and nonuser groups. For nonuser groups, their main income sources were from trading (44 %), wage labour (32 %) and forest resources(23 %). In contrast, the Lantana user groups substituted their loss of income from forest resources (7 %) by income from Lantana(46 %). The ecological history revealed that Lantana was adopted as a resource at a time when it was increasing in the landscape and traditional bamboo resources were in decline because of overuse by commercial enterprises and mast flowering. This change in ecological resource availability prompted amajor shift in livelihoods for some in the area.